Abstract In a few short years of life, children go from almost no knowledge of the sounds of their language to a rich knowledge, yet their speech production may not be adultlike until age 8 or later. How well does production approximate perception, and what contributes to perceptual representations? Most studies focus on adult input, but children also receive substantial child input (as much as 45% of total input), including their own vocalizations. The need to account for a major source of speech input, and lack of clarity about perception-production relationships, represent major theoretical gaps. We hypothesize that initially, adult-based percepts shape child production. Errorful child productions, due to motor difficulty matching targets, are then learned and may guide production and recognition. Goal. The goal of the proposal is to innovate a test of perception-production relationships in children which is both sensitive to recognition difficulty and natural for young children. Method. We innovate a paradigm to test a child's understanding of their own speech. We audio-record the child naming familiar pictures, then show them sets of pictures as they hear their recorded labels. Eye movements to pictures provide a sensitive, natural measure of recognition effort. Specific Aims SPECIFIC AIM 1 is to establish a new paradigm to test comprehension of one's own speech. SPECIFIC AIM 2 is to test the Articulatory Error Hypothesis, that children's inaccurate productions result from imperfect motor realizations of perceptual representations. If so, children should comprehend adult speech better than they comprehend their own speech (STUDY 1). SPECIFIC AIM 3 is to test the Multiple Representations Hypothesis, that children simultaneously possess not only adult but also self-speech representations. If so, then the child should understand their own speech better than another listener understands that child's speech (STUDIES 2-3). Significance. We innovate a methodology to assess perception-production relationships, and begin to account for an underexplored source of speech input. Findings may suggest a new route? perceptual training on child speech?for intervention in speech sound disorders, which affect 4% of young children and which impair communication, academics, and social interaction.